json.RawMessage to sdk.Msg

json-raw-message-to-sdk-msg.go

package main

import (
	"encoding/json"
	"fmt"
	"reflect"

	"cosmossdk.io/simapp"
	"github.com/cosmos/cosmos-sdk/codec"
	codectypes "github.com/cosmos/cosmos-sdk/codec/types"
	sdk "github.com/cosmos/cosmos-sdk/types"
	banktypes "github.com/cosmos/cosmos-sdk/x/bank/types"
)

// this is the json raw message we want to unmarshal
var rawMsg json.RawMessage = []byte(`
	{
		"@type": "/cosmos.bank.v1beta1.MsgSend",
		"from_address": "cosmos1f3ugm8xjcq0g5acgp5smpu940f9pzk5d50c608x8r7nenyjyl0lszukf5v",
		"to_address": "cosmos1qskahqekuvwmyqgmusfdlg62eptczc4rd05mc2",
		"amount": [
			{
				"denom": "utoken",
				"amount": "12345"
			}
		]
	}
`)

func main() {
	// initialize an empty interface registry
	ir := codectypes.NewInterfaceRegistry()

	// register basic cosmos-sdk interfaces
	simapp.ModuleBasics.RegisterInterfaces(ir)

	// create codec
	cdc := codec.NewProtoCodec(ir)

	// json raw message --> any
	var any codectypes.Any
	if err := cdc.UnmarshalJSON(rawMsg, &any); err != nil {
		panic(err)
	}

	// any --> msg
	var msg sdk.Msg
	if err := ir.UnpackAny(&any, &msg); err != nil {
		panic(err)
	}

	// check whether the unmarshaled msg is correct
	expected := banktypes.NewMsgSend(
		sdk.MustAccAddressFromBech32("cosmos1f3ugm8xjcq0g5acgp5smpu940f9pzk5d50c608x8r7nenyjyl0lszukf5v"),
		sdk.MustAccAddressFromBech32("cosmos1qskahqekuvwmyqgmusfdlg62eptczc4rd05mc2"),
		sdk.NewCoins(sdk.NewCoin("utoken", sdk.NewInt(12345))),
	)
	fmt.Println("equal?", reflect.DeepEqual(msg, expected))
}